# R1+R2 Zs Ze Calculator — Calculate R1+R2 or Zs. > Electrical impedance calculator for R1+R2, Zs, and Ze values. (iPhone/iPad app by Pro Certs Software Ltd.) - Source: https://appshunter.io/ios/app/r1-plus-r2-zs-ze-calculator/id572416784 (this page in markdown: same URL + `.md`) - Developer: [Pro Certs Software Ltd](https://appshunter.io/developer/444429696) - Category: Utilities, Productivity - Price: Free - Age rating: 4+ - Requires: iOS 12.0 · 12 MB - Languages: American English - Released: 2012-11-02 - Data updated: 2026-08-24 - Monetization: ad-supported - User reviews in markdown: https://appshunter.io/ios/app/r1-plus-r2-zs-ze-calculator/id572416784/reviews.md ## What is R1+R2 Zs Ze Calculator? Calculates R1+R2, Zs or Ze, input two values to calculate the third. - Calculate: Zs - Calculate: (R1+R2) - Calculate: Ze (not recommended) A quick and easy way to calculate R1+R2 or Zs. Check your measured R1+R2 or Zs values with this handy R1+R2 calculator or calculate a value from the other two known values to verify actual measurements obtained. Easily calculate the earth loop impedance (Zs) from the R1+R2 and Ze values, also calculate the R1+R2 value from the Zs and Ze values. + Check you measured R1+R2 readings + Check your measured Zs readings + Validate or verify your Ze (not recommended) Although this app allows the calculation of the Ze value, the Ze value should not be calculated. The Ze value should be obtained by actual measurement or by inquiry to the regional electric company. It is good practice to directly measure R1+R2 and Zs values rather than calculating them. How to calculate Zs: 1) Enter the Zs and R1+R2 values. 2) Tap calculate. How to calculate R1+R2: 1) Enter the Zs and Ze values. 2) Tap calculate. How to calculate Ze: The Ze value should not be calculated, instead obtained by direct measurement or by inquiry to the electricity network company. ## Key features - Calculate Zs - Calculate R1+R2 - Calculate Ze (with caution) - Verify measured readings - Input two values to find the third ## Recent user reviews (10 of 10) All indexed reviews: https://appshunter.io/ios/app/r1-plus-r2-zs-ze-calculator/id572416784/reviews.md ### 5/5 — Great app *2021-05-19* Simple helpful app to make calculations faultless ### 2/5 — Not good *2018-08-24* I agree with Basic Math if you need this app you definitely need a knew job ### 1/5 — Update *2018-01-09* Unfortunately this version does not work on the iPhone **Developer response:** App now updated for iOS 11 & new UI redesign. ### 1/5 — Basic math *2016-10-27* If you need this app to do the calculations this app does, you need to find a new job. Basic math that most electricians could do in their head. ### 2/5 — Hhmm *2013-05-31* As mentioned by "22w" the ze calculation is wrong. This should be measured!! **Developer response:** App now updated for iOS 11 & new UI redesign. ### 1/5 — Oo *2012-12-10* Not a good app. As a calculator to add Ze to [R1+R2] to obtain Zs it's ok. But to use the calculation Zs - [R1+R2] as this app does to obtain Ze is wrong. Ze is either obtained by enquiry from the DNO, or measured with the system isolated, and with all bonding disconnected. Ze is the External EFLI. **Developer response:** App now updated for iOS 11 & new UI redesign. ### 5/5 — Very good app. *2012-11-22* Great app, very useful and handy. ### 5/5 — Ze + Zs (R1 + R2) calculator *2012-11-10, version 1.0* Great little app. Very handy. ### 5/5 — Zs Ze app *2012-11-05* Great app, very useful. 5 stars! ### 5/5 — Very good *2012-10-31* Great app and very useful. ## Frequently asked questions about R1+R2 Zs Ze Calculator ### What can R1+R2 Zs Ze Calculator do? R1+R2 Zs Ze Calculator allows you to calculate R1+R2, Zs, or Ze values by inputting two known values. It's designed to help verify measured electrical readings. ### Does R1+R2 Zs Ze Calculator have ads? Yes, R1+R2 Zs Ze Calculator contains advertisements. It is a free application supported by ads. ### Is R1+R2 Zs Ze Calculator recommended for calculating Ze? The app states that calculating Ze is not recommended. It advises obtaining the Ze value through direct measurement or by inquiring with the regional electric company. ### What devices does R1+R2 Zs Ze Calculator support? R1+R2 Zs Ze Calculator is available for iPhone, iPad, and iPod devices. ### How often is R1+R2 Zs Ze Calculator updated? The latest version of R1+R2 Zs Ze Calculator is 4.3.7, which was last updated on July 28, 2025. This indicates regular updates. ### What is the age rating for R1+R2 Zs Ze Calculator? R1+R2 Zs Ze Calculator has an age rating of 4+, making it suitable for a wide range of users. ### Can I use R1+R2 Zs Ze Calculator offline? The provided data does not specify offline functionality. However, as a calculation utility, it is likely to function without an internet connection. ### How do I calculate Zs using R1+R2 Zs Ze Calculator? To calculate Zs, you need to enter the known Zs and R1+R2 values into the app and then tap the calculate button. ## Version history (last 5 releases) ### 4.3.7 — 2025-07-28 27/07/2025 v4.3.7 - UI improvements ### 4.3.3 — 2022-04-06 Updated app icon and a few minor tweaks. ### 4.3.2 — 2022-01-17 News feed update. ### 4.3.0 — 2021-11-07 Some basic house keeping and function improvements. Added a news feed from our blog. ### 4.2 — 2020-04-29 Version May 2020: New user interface (UI) ## Apps similar to R1+R2 Zs Ze Calculator | App | Rating | Price | Category | | --- | --- | --- | --- | | [CertSuite](https://appshunter.io/ios/app/certsuite/id1567220288) | — | Free | Utilities | | [Electrical Certificate App](https://appshunter.io/ios/app/electrical-certificate-app/id1531731405) | — | Free | Utilities | | [PAT Test Pro](https://appshunter.io/ios/app/pat-test-pro/id6746668717) | — | Free | Utilities | | [Super Rod Super Cam](https://appshunter.io/ios/app/super-rod-super-cam/id1614755108) | — | Free | Utilities | | [Rolec Connect](https://appshunter.io/ios/app/rolec-connect/id6742486045) | — | Free | Utilities | | [BG SyncEV Installer](https://appshunter.io/ios/app/bg-syncev-installer/id1613505641) | — | Free | Utilities | ## More apps by Pro Certs Software Ltd - [Watts Amps Volts Calculator](https://appshunter.io/ios/app/watts-amps-volts-calculator/id450813841) - [kVA Calculator](https://appshunter.io/ios/app/kva-calculator/id467407057) - [Max Zs Values](https://appshunter.io/ios/app/max-zs-values/id498838137) - [Electrical Tools and Reference](https://appshunter.io/ios/app/electrical-tools-and-reference/id564264558) - [Fault Current Calculator (PFC)](https://appshunter.io/ios/app/fault-current-calculator-pfc/id577611194) All apps by Pro Certs Software Ltd: https://appshunter.io/developer/444429696 ## Related topics [1plus](https://appshunter.io/ios/topics/1plus) --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-24.*